The present invention relates to supplying a consumable welding wire electrode to the welding gun used in a welding operation wherein the location of the welding operation does not remain constant. This can include welding operations at job sites which change day to day or welding operations covering large areas at a single job site. Portable wire feeders are known in the art and are generally shown in Bellefleur U.S. Pat. No. 4,665,300; Rybicki U.S. Pat. No. 6,213,375; Kroll U.S. Pat. No. 4,508,954; Chandler U.S. Pat. No. 6,225,596; Miller U.S. Pat. No. 5,410,126 and Grimm U.S. Pat. No. 5,836,539. These patent are incorporated by reference herein as background information illustrating portable wire feeders.
The present invention is particularly applicable for use in connection with shipyard welding and, therefore, the invention will be shown and described with particular reference thereto. However, the invention has much broader application in that it can be used as a portable wire feeder for many applications involving different types of job sites and welding operations.
It is, of course, well known that wire can be used as an effective welding consumable. Welding wire forms a part of the welding electrode and contributes to the weld pool as filler material. Therefore, the wire feeder needs to supply the welding operation with the welding wire in a consistent and controllable manner. Furthermore, in order to maximize the benefits of utilizing welding wire, the wire must be accurately directed to the weld point of the welding operation at a controlled rate.
The portable wire feeder must supply the welding operation with the welding wire in a consistent and controllable manner like a standard stationary wire feeder even though it must be capable of repeated movement and use in connection with a wide range of work environments, many of which can be severe. Therefore, the portable wire feeder must not only provide accurate and continuous wire control, it must have additional characteristics not found in stationary wire feeders that are used in controlled environments such as a work shop or factory floor. One such characteristic is that the portable wire feeder must be compact and light weight. Since the portable wire feeder is repeatedly moved, it is advantageous for the portable wire feeder to be lightweight. Furthermore, since on site jobs require the user to haul their tools in a fixed and many times limited space, a compact size is advantageous.
The portable wire feeder must be rugged. While the traditional wire feeder is typically used in one location over a long period of time, the portable wire feeder is constantly moved and subjected to many adverse conditions. Merely moving the portable wire feeder subjects it to impact forces by the underlying surface when it is placed on the surface and when it is transported in a work vehicle. Furthermore, each time the portable wire feeder is moved, there is a risk that the feeder will be dropped or impacted by other objects. Finally, the portable wire feeder is often used in harsh work environments.
The portable wire feeder must be easy to use even when the user is wearing protective gear. The user of a welder typically wears, among other protective gear, gloves and face/eye protection. Therefore the portable wire feeder should be easy to grasp and manipulate even with protective gloves. This includes the ability to easily manipulate the portable feeder over uncertain terrain often associated with many job sites and easily load the feeder onto a work vehicle. Furthermore, due to the uncertainty relating to the underlying surfaces, the portable wire feeder must be stable over a wide range of surfaces. This is especially important since the portable wire feeder is often pulled across the underlying surface by its wire guide tube. The controls must also be easily accessible and controllable by the user wearing protective gear and must be rugged.
The supply of welding wire needs to be easily replaceable under a wide range of conditions and protected against the elements of a harsh work environment. These characteristics often conflict. In this respect, providing protection for the welding wire typically involves a barrier between the wire and the environment. This can prevent easy accessability to and replacement of the welding wire. It is also advantageous to utilize a standard spool of welding wire in order to reduce cost and simplify wire replacement. This can increase the size of the portable wire feeder. Furthermore, providing easy access to an internal wire spool compartment can weaken the overall rigidity of the portable wire feeder.
Prior art wire feeders and portable wire feeders do not include these characteristics. In this respect, referring to the Chandler patent, a portable welding unit is disclosed which includes a wire feeder. While Chandler""s device is compact, it does not provide protection for all of the components of the wire feeder. As a result, these components can be damaged during use or during the transportation of the feeder to and from the job site. Furthermore, the Chandler device is not easily stored or manipulated over non-flat underlying surfaces due to its narrow base design. The wire feeder disclosed in Bellefleur also is compact. However, Bellefleur""s wire feeder is not easily transportable and it does not provide protection for the controls. Bellefleur also fails to disclose a rigid frame to prevent impact damage. The Miller patent discloses a portable wire feeder which also fails to provide protection for the controls. In fact, the Miller controls are on an outside edge without protection. Furthermore, Miller""s feeder does not include any means for easy movement or manipulation. Another disadvantage associated with the Miller device is that access to the wire supply is restricted.
In accordance with the present invention, provided is a portable wire feeder is provided for use in connection with shipyard welding operations which includes a frame structure that supports the portable wire feeder on a wide variety of underlying surfaces and protects the internal components from impact while allowing easy access to the internal components, and easy transportation and use of the portable wire feeder. In this respect, a portable wire feeder in accordance with the present invention includes a lightweight yet rigid outer frame structure that is configured for stability. The outer frame further includes accessible grasp points and selectively engageable covers for protecting the internal components while providing easy access thereto.
The outer frame of a wire feeder according to the present invention defines a rigid outer perimeter. The frame includes a non-parallel base rail structure wherein the base rails are spaced apart and extend away from one another near the rearward end of the frame such that the base is widest at its rearward end. Since the rearward end is also the heaviest portion of the portable wire feeder, the weight of the feeder is concentrated over the widest portion making the structure more stable. Furthermore, this configuration also minimizes tipping when the feeder is on uneven surfaces or when it""s pulled by the wire guide tube that extends out its forward end. The frame further includes sides which extend upwardly and toward one another. This configuration lowers the center of gravity which further increases the stability of the portable wire feeder. In addition, the frame includes front and back portions that protect the internal components and which include access openings for certain internal components. The frame further includes handles for moving and transporting the portable wire feeder with either one or two hands.
In accordance with another aspect of the present invention, the portable wire feeder includes multiple covers for selectively covering the control box and the wire spool. Both covers are configured to be easily opened and closed even with a gloved hand. Furthermore, these covers can include transparent panels to allow the user to monitor the control box and spool while welding. The control box includes gauges and/or controls for the wire feeder and/or the welding operation and which gauges and controls can be damaged from welding spatter or from impact by other objects. The control box cover is pivotal relative to the frame between an opened and a closed position wherein the gauges and/or controls are protected while in the closed position. Even though the control box and cover are positioned near a center handle for convenience of operation, both are sufficiently spaced from the center handle to allow the user to easily open or close the cover with a gloved hand even while the user supports the feeder by the center grasp handle. The wire spool cover also moves relative to the frame between an opened and a closed position. The spool cover provides protection similar to the protection provided by the box cover.
In accordance with even another aspect of the present invention, the portable wire feeder includes a spool support that is easily accessible without weakening the frame and without complicating the replacement of the wire spool. In fact, the spool support according to the present invention actually strengthens the frame structure of the portable wire feeder. As stated above, the welding wire is consumable and, therefore, the wire spool must be replaced as the wire is depleted or when the type of wire is changed. The spool support must therefore include a spindle with at least one free end that can receive the wire spool. The spindle according to the present invention has a first end rigidly connected to the frame and a second end which is free to receiving the wire spool. However, the second end includes a latch mechanism that can interengaged with a pivotal frame component such that both ends of the spindle are supported on the frame when latched, and the spindle acts as an additional frame component. The spool support is preferably positioned near the rearward end for increased stability and to prevent the wire spool or support from blocking access to the control box.
In accordance with yet another aspect of the present invention, the portable wire feeder includes multiple handles spaced on either side of the center of gravity of the portable wire feeder. This allows for two handed and balanced lifting which makes the feeder easier to transport. More particularly, the two handles are spaced from one another on either side of the heavy wire spool. One handle is positioned between the rearward end and the spool axis and the other handle is more centered and is between the forward end of the feeder and the spool axis. The center handle is also closer to the actual center of gravity so that the user can use his/her free hand for other purposes such as to operate the controls. In addition, the handles are also structural components of the frame to further strengthen the frame without adding unnecessary weight.
In accordance with a further aspect of the present invention, the portable wire feeder further include wheels which can engage an underlying surface to allow the feeder to freely roll on the surface. Since easy movement is not always advantageous, the wheels can be designed for varying degrees of movement of the feeder. The first configuration allows for continuous wheel engagement which allows the feeder to freely move on flat surfaces at all times. A second configuration allows for the wheels to engage the underlying surface only when the front of the feeder is raised. This configuration allows for easy movement only when desired without modification to the wheels. The third configuration is a combination of the first two. With respect to the second configuration, the frame includes an upwardly extending portion which supports the wheel axles such that the axles to are spaced sufficiently above the bottom of the base so the wheels do not engage the underlying surface when the base is resting flat on the surface. Engagement by the wheels is initiated only when the forward end of the feeder is lifted upwardly relative to the rearward end. This allows the user to decide when the portable wire feeder is to be free to roll on the underlying surface and when it is to be stationary. In the third configuration, front casters are provided which are pivotably connected to the forward end of the base for movement about a horizontal caster axis between an operating position and a retracted position. When the casters are in the retracted position they are spaced from the underlying surface when the bottom of the feeder is resting on the surface. However, when the casters are in the operating position, the bottom of the feeder is spaced from the underlying surface and the casters engage the surface similar to the first configuration. This allows the user to quickly adapt the feeder between a highly mobile feeder and a stationary feeder.
In accordance with even another aspect of the present invention, the portable wire feeder includes a control box that can be removed from the feeder. This provision allows the portable wire feeder to be operated remotely thereby preventing the user from having to return to the feeder to make an adjustment during the welding operation.
The primary object of the present invention is the provision of a portable wire feeder which is light weight yet rigid so that it can be easily transported and withstand many adverse conditions.
Another object is the provision of a portable wire feeder of the foregoing character which is easy to maneuver yet is capable of being maintained in a set position.
Still another object is the provision of a portable wire feeder of the foregoing character which includes at least two handles spaced on either side of the center of gravity for the portable wire feeder.
A further object is the provision of a portable wire feeder of the foregoing character wherein one of the handles is near the center of gravity for the portable wire feeder so that one hand can be used to support the feeder while the other hand can operate controls on the feeder.
Yet a further object is the provision of a portable wire feeder of the foregoing character which includes a spool support for a wire spool that allows full and easy access to the wire spool while also acting as a structural component of the frame when latched.
Still another object is the provision of a portable wire feeder of the foregoing character which includes wheels that are selectively engageable with an underlying surface.
Still another object is the provision of a portable wire feeder of the foregoing character wherein the wheels are attached to fixed axles that are spaced above the base of the frame such that the wheels only engage the underlying surface when its forward end is lifted relative to the rearward end.
Yet a further object is the provision of a portable wire feeder of the foregoing character which includes casters on the forward end of the base which are retractable such that they pivot between an operating position wherein the casters and the wheels engage the underlying surface and a retracted position where the caster and the wheels are spaced from the underlying surface as the bottom of the frame rests on the surface.
A further object is the provision of a portable feeder of the foregoing character which includes a control box cover which is pivotal between an open and a closed position wherein the user can grasp the handle nearest the control box in one hand and operate the box cover and the controls with the other hand.
Yet another object of the present invention is the provision of a portable wire feeder of the foregoing character which includes a retractable spool cover which protects the wire spool and which can be quickly retracted to gain access to the wire spool.
Another object of the present invention is the provision of a portable feeder of the foregoing character which includes a base that is wider near its rearward end thereby making the portable wire feeder more stable.
Yet a further object is the provision of a portable wire feeder of the foregoing character wherein the center of gravity of the portable wire feeder is set low and near the rearward end near the widest portion of the base making the portable wire feeder stable on a wide variety of surfaces.
Even a further object is the provision of a portable wire feeder of the foregoing character which includes a control box that is removable from the portable wire feeder allowing the user to control the wire feeding and/or the welding operation from a remote location.
Another object is the provision of a portable wire feeder of the foregoing character which utilizes components that are economical to manufacture, easy to use in the field while still being light weight and durable.